billyg5829

My Feedback: (10)

I've heard so many theories on what type of Gas and oil combinations to use during and after breakend. example BME states to use 100LL and Redline racing oil @ 50/1 from the onset.
DA says to use 92 + and staright oil, then switch to Redline after breakend.
Who is using What and without Failures..[:@]

gboulton

My Feedback: (15)

I've used 93 octane, Ethanol free, with Klotz Model Lube at 32:1 for 9+ gallons in a DLE 111 since the first flip, 100+ flights, no problems, plugs looked good during the last check at 8gal.

rcairflr

My Feedback: (44)

We recommend standard 87 octane unleaded gasoline for your BME (Chevron and Texaco seem to work very well). Higher-octane fuel will not generate more power and may cause the engine to run slower and overheat. Try what is recommended first!

The above is out of the BME 116 manual

Fuel and Oil Mix
• Mid to High octane gas is recommended (This is out of my DA-100 manual.


My DA-85 manual says to use "Low octane pump gasoline is recommended, Higher octane gasoline can actually lower performance"

My DA-50 manual says "Low to mid octane pump gas is recommended"

So where are you getting 100LL for BME and 92+ for DA?

My opinion is go by what the manual says, not by what you hear unless it is a very credible source.

w8ye

My Feedback: (16)

100LL has less oil content than automotive varieties. Plus it has lead

I would be afraid to use it.

av8tor1977

My Feedback: (6)

The lead will definitely cause increased deposits on the piston, head, etc., and can also cause spark plug fouling. The power would be down somewhat as well.

Everyone thinks that "High Octane Avgas" is the ticket to more power. It could be, but only if the engine was designed for it and had increased compression, etc. If it is used in an engine designed for a lower octane fuel, it is actually detrimental. I just love the movie and/or news headlines that say or insinuate, "Hundreds of gallons of HIGH OCTANE AIRPLANE FUEL caused a huge explosion." Higher octane fuel actually burns SLOWER, and is less likely to explode. It is a pure and unfounded myth that airplane fuel generates more power, in and of itself.

AV8TOR

LanceLKs

BME does recommend 100LL for their engines . They are seeing lots of problems from ethanol in the fuel and all gas station fuel has some ethanol in it, some more than others. The 100LL has no ethanol and is a more consistant blend than others. Its not about the octane , its the absence of ethanol .

captinjohn

Just get a good grade of pump gas. Read what Tired Old Man says, and others. 100LL is not needed. Look for a good grade of pump gas.

WildeOne

My Feedback: (1)

No one has commented on oil, so I will. Use only 2S aircooled engine oil, typically found at engine repair shops, chain saw dealers, etc. There are important differences between those oils and TCW-3, trypically used for water cooled 2s motors (outboards, etc.) I use a 2s Penzoil brand, and I'm sure there are a number of others. 40:1 is fine after breakin.

For gas, typical 87 octane is fine for most motors.

Jim

Truckracer

My Feedback: (19)

And .... there is a problem with oils rated API-TC which is still the most common rating for air cooled 2 stroke oils? Pennzoil has this API rating.

BigExtra

I this we should expand on this.
I would like to know if anyone has had a failure that the manufacturer claims it was due to
type of oil and gas used.
I will start:::
My first gas was one of the first ZDZ 80 RV from RC Showcase back in 97 - 98
Back then they were not even sure what to run in that engine. So the instructions were not very clear.
So what everybody else back then was using was Klotz, so I tried it. Was that a big mistake!!
After about 10 flights the engine failed to start. I packed it up and sent it back to RCS and they called me
and asked what gas and oil I was using, I told them, and of course I made the wrong oil choice.
The rings and pistons had carboned up and stuck the rings. They replaced the rings and cleaned it up.
That was when I started running petrolleum based oil from breakin on.
By the way, that same engine is still running today in a plane I sold billyg5829
Engines I have to Date are:
DA 150 no oil failure, only reed failure
BME 110 no oil failure, only reed failure
ZDZ Super80 no oil failure
ZDZ 80RV no oil failure
ZDZ 60 no oil failure
ZDZ 40 no oil failure
Fuji 43 EI no oil failure
I run high octane gas 92 to 93 and what has been the oil I have ran for years with no problems in all of these engines.. STILH 100% PETROL BASED OIL mixed 50-1

Tired Old Man

My Feedback: (1)

Any pump grade gas at a name station is just fine for most engines. There are a few where a higher compression ratio dictates a higher octane, but none of them need more that premium grade pump gas. No exotic fuels are ever needed.

Oils are pretty simple. Almost any of them work well if used in enough quantity. Those more concerned with avoiding any bottom of the plane clean up than with engine performance and longevity are typically the ones that like the lean oil ratios and generally are the ones that suffer the most long term consequences in their engines.

So there's no hoodoo, voodoo, or magic to having a great performing engine. If what you are told makes sense, it's likely the right information. If what you are told seems to be contrary to what you think is right, it's likely not the best thing to do. Tune it well, and provide some colling inlet and exit methods and enjoy.

RTK

My Feedback: (1)

As has been mentioned, use 87 octane unless your engine requires higher, run any quality oil (synthetic or not) in the ratio of 32:1 to 50:1 as is recommended by the OIL manufacturer. Also if you run a pipe and it is hot in the summer bump up a couple of octane.

I have run various synthetics and non synthetics and different octane ratings without any mechanical failures to date, just stay away from those 100:1 ratios. One last thing, do not mix different oil together in the same jug, you can run into compatibility problems.

rc bugman

My Feedback: (30)

Hi,

I have found that 3w engines benefit from higher octane fuel. The book says 89 but I always run 91-92 which ever is available. There is usually a 200-400 rpm gain with the higher octane fuel over 87.

Back in the early days before I knew better, I used to run synthetic TCW-3 oil in my 3W engines. No engine failures at 50:1 and the engines were sparkling clean. The only problem was the clogging of the small holes in the muffler from carbon formation. I even made a special tool to unclog the holes in the spring before a flying season.

Now, I use Pennzoil air cooled at 40:1 with excellent results. If the oil has been discontinued when I use up my supply, there are other excellent oils available.

Elson

RTK

My Feedback: (1)

Elson,
Shell, the parent company of Pennzoil, is coming out with an new designed oil for 2 stroke motors to replace Pennzoil air cooled. I believe it will be called shell aero sport 2

az3d

My Feedback: (59)

I have a new BME 116 and run 100LL. I spoke with Tom at BME and the 100LL makes sense to me. First the fuel is cleaner, no additives (in Phoenix we have a lot of ethonal added) and it does not have crud in it. Anyone other than me cleaned out a clogged carb? The 116 is a stroked 110 so it has higher compression, significantly more than a DA. The other thing Tom said that made sense is you pay a lot of money for the engine, what is another dollar a gallon. Added bonus, 100LL is a cool blue color. I am in the process of breaking mine in on lawn boy and then switching over to red line. A tech at red line told me I could break my engine in on it but he recommended a petrolium based oil instead. As far as the engine getting to hot I baffled mine and we checked it right after landing and it was 210 degrees. Baffeling works. When I had a 110 I ran pump gas with no problems, now that I have a 116 its 100LL all the way. Just my 2 cents.

Jezmo

I have personally run 100LL for about 100 hrs in a DA50 mixed 40:1 with Redline Two Stroke Racing oil. The engine was fresh when we started out and after the 100 hrs was torn down for inspection. There was some soft carbon in the top of the combustion chamber (roughly 15-20% covered) and also some very soft carbon on top of the piston that could easily be removed with a shop rag soaked in gasoline. The piston had clean spots about 1/2 to 3/4" long inline with the inlet ports extending in towards the center of the piston. The side of the piston from the ring down was clean and shiny as was the ring groove. After cleaning we reassembled it and have been running it on 93 octane ethanol free MoGas mixed 40:1 with Stihl HP Ultra. (I am getting the fuel from a Marina) Haven't had it apart since the switch but looking in through the plug hole, it looks spotless with absolutely NO carbon on the piston crown.

P.S. I also tached it with both fuels, with the same exact prop, and found less than 100 rpms difference.

Kelly Models

My Feedback: (1)

I have several gas engines. I've broken most of them in with Lawn-boy 32:1 on 87 octane. After 2-3 gallons I switched to Amsoil Sabre Pro and ran several more gallons at 50:1. Last season I was mixing the Amsoil at 80:1. I've heard alot of good and bad mixing oils this lean and after a little research, a few of us have decided to switch to Redline Racing Oil mixed at 50:1 for this year. I've read alot of comments on the use of this particular brand and I'm sure I will be happy with the results. I have one question. I just got my DA-50 back from Desert Aircraft. They did a total rebuild, (new cylinder, piston, rings, bearings, etc.) I don't blame the use of Amsoil for the breakdown. I'm sure something got into the engine to cause all the damage. Should I break the engine in on Redline at 24:1 or should I use the Lawn-boy oil that I used in the past? There isn't alot of discussion on what's better to lap the rings in.

Tired Old Man

My Feedback: (1)

Run the engine using the Redline at 32-1. Give it a few hours of flight time then change the ratio to 40 or 50-1.

3DDino

ive only 95 & 97 octane over here
since high octane burns slower than that of the 87octane
could i just advance the timing so as to compensate for the slow burn of high octane gas ?
thx

RTK

My Feedback: (1)

I wouldn't

3DDino

why wouldn,t you
it makes sense
thx

w8ye

My Feedback: (16)

The timing runs best at 28 dgrees before top dead center above 4000 rpm and that is it no matter the compression or fuel

You fuel's octane rating is measured by the research method only which reports it as being higher than in the states which report the octane rating as Motor + research method /2

RTK

My Feedback: (1)

I know people that have run tests and as stated in the previous post there is no advantage in power. In fact you can cause detonation and heat which will reduce power.

3DDino

thx for the info

Tired Old Man

My Feedback: (1)

Anywhere between 26 and 30 degrees btdc works just fine. The higher octane won't have any noticable effect on performance, power, or generated heat. Upping the advance WILL generate more heat. It changes more than just the ignition advance. It also changes the mixture relationship with the port timing. I've been doing a lot of point by point advance curve experimentation over the past few months and the results have been most enlightening.


BTW,

For all you BME 58 and 115-116 users out there, use the premium grade gas. You have a high compression engine.